1. Field of the Invention
The present invention relates to a portable communication terminal device and a character/image display method for enabling input of characters by operations through predetermined keys or a dial.
2. Description of the Related Art
Along with further diversification of services rendered by business operators such as Internet providers, for example, not only for mutual telephone communication, but portable telephone devices are also utilized as data terminal devices for exchanging letter information typically represented by E-mail communication, and yet, users of such portable telephone devices have extraordinarily increased in recent years.
Under such circumstances, every user of portable telephone devices actually encounters such a problem how to efficiently perform key input operation via a compactly configured portable telephone device having a limited number of input keys (buttons) with such a limited area of display screen. Because of this, in any of conventional portable telephone devices, each key is allocated with a plurality of operating functions and characters which are respectively subject to switching per operating program and mode.
Nevertheless, introduction of the above-mentioned switching method obliges every user to perform more operating steps and shift more operating modes than that is normally required for a personal computer fitted with a full-scale keyboard. In other words, whenever utilizing such a conventional switching method, users are obliged to depress an identical input key for plural rounds until an objective character is eventually input. In order to deal with this problem, there is such a character input method based on a predictive conversion method described below.
The predictive conversion method is characterized by such a method which enables an operator to optionally select a target word by executing serial steps including an initial input of readable Japanese “kana” syllables followed by a step of detecting certain words starting with a pattern of a single or several “kana” syllables corresponding those already being input and a final step of displaying the detected words as the predictive candidates. According to the method, the operator can select the target word without inputting all the “kana” syllables to be converted. Further, after entering a certain word, by way of displaying a successive phrase candidate as the predictive candidate, the operator is enabled to input a certain sentence merely by way of selecting a phrase candidate within such a scope in which phrase candidates can be combined with each other, even when the operator does not input any “kana” syllables at all.
As mentioned earlier, due to critical consideration on portable convenience with compact size and light-weight, any of conventional portable telephone devices is provided with a small display area and a limited number of input keys without being able to execute direct pointing via pen-touch, and as a result, it is quite difficult for any user to efficiently perform input of those words requiring conversion of “kana” syllables into corresponding Chinese characters. In particular, the above-referred existing method for allocating each of input buttons with a plurality of functions and characters in combination with each other by way of obliging every user to continuously depress a specific input button has already been accustomed and substantially standardized by a large number of existing users. Because of this, introduction of a new input method largely deviant from the existing method will cause users to be confused to consequently raise a problem.
On the other hand, even though the above referred predictive conversion method provides such an advantage in that highly compatible phrase candidates can be listed up at real time without performing a trigger input, that is, any “kana” input, this method still raises a problem in that user can hardly control the timing to list up the phrase candidates, and instead, list of the phrase candidates is displayed regardless of the user's intention.
Further, according to the predictive conversion method, there are two fields including the one used for inputting characters and the other one for listing up words and/or phrase candidates. In such a portable telephone device incapable of performing direct positioning, such a cursor for designating the actual input/selected position is required for each field. However, if there is merely a single operating device for shifting the cursor, it is not certain for any user to identify which cursor should be shifted at a specific timing while operating the device, thus raising a problem.
Further, while executing the predictive conversion method, independently of user's will (trigger), a list of convertible candidates and the phrase candidates to follow a character is displayed. For example, two kinds of scenes may be generated simultaneously including the one in which character cursor should be shifted in the upward and downward directions and the other one in which a cursor should be shifted in the upward and downward directions even in a case in which convertible candidates are displayed on the display screen. As a result, if there is merely a single operating device for shifting cursor in the upward and downward directions, it is required to dividedly allocate cursor to deal with both scenes, thus raising another annoying problem.